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Leaking Boiler? How to Fix a Boiler That is Leaking From the Bottom

Finding water leaking from the bottom of your boiler is an unwelcome and worrying sight! Rather than panicking, take a few minutes to read our guide and find out more about leaks on all types and makes of boilers.

Can My Leaking Boiler Be Fixed?

The first question that will probably spring to mind is whether your boiler can be fixed or not, followed quickly by the stress of wondering how much a Gas Safe engineer will charge to resolve the problem.

If you are keen to find a quick solution, then Fernox F4 could be the answer. F4 is a specially designed solution for leaking boilers and works to provide a leak-sealing solution that can stop your leak within just a couple of hours. If it hasn’t worked within 24 hours, then you will know that the only way to proceed is to call out a Gas Safe engineer.

How Dangerous is a Leaky Boiler?

No matter where the water is coming from, a leaking boiler can be dangerous as the water can get onto electrical components and cause the boiler to break down completely. Water being ejected from the system will also drop the pressure of your boiler, stopping the system from running properly and causing each comment to work harder than it should to produce the heat and hot water you need. In short, if your boiler is leaking, you must arrange a repair as a matter of urgency.

Why is My Boiler Leaking Water From the Bottom?

There are a number of faults that can cause your boiler to leak from the bottom, and the first step for any engineer is to figure out the source of the leak so that it can be repaired. Some of the most common sources include:

  • The Heating Pump if your heater pump is the source of the leak, then your seals have either completely deteriorated over time or have blown due to excessive pressure being placed on them. 
  • The Pressure Release Valve if the pressure of your boiler is above 2 bar, then the system will try to release excess water in a bid to drop the pressure. This problem typically occurs when too much water has been added to the filling loop, causing it to eject the water to save the rest of the system from becoming damaged.
  • The Heat Exchanger as a heat exchanger gets older, it often corrodes and can even split, allowing water to pass through and escape from the bottom of the boiler. If this happens, then you will need to replace your boiler unless your current one is still under the manufacturer’s warranty.
  • The Auto Air Vent as with the pressure release valve, the auto air vent will try to reduce the pressure if it is too high. Unfortunately, as it tries to release pressure, the valve can become stuck and end up releasing water out of the boiler rather than just excess air.
  • The Pipe Work it’s not always the boiler itself that is the issue, and can sometimes be old, damaged or corroded pipes and pipe fittings that are the source of the leak. 
  • The Boiler Connections finally, in rare cases, the boiler connections could have been incorrectly set up, allowing water to escape. To resolve this issue, simply wipe the water away and check if it reappears. If so, tighten the connections with a quarter turn to see if the leak stops.

I Know Why My Boiler is Leaking – How Do I Fix It?

Finding the source of the leak is the first step, but getting it fixed is the next. In reality, some leaks can be quickly and cheaply fixed, but others can be incredibly expensive and may require a complete boiler replacement. The one thing that all of these problems have in common is that they need to be fixed by an appropriately qualified, Gas Safe engineer.

During the visit, your Gas Safe engineer will diagnose the problem, provide you with a quote to fix the issue and be able to advise you on whether repairing the boiler is the best way forward or not. If it’s decided that your boiler needs to be replaced, then you should shop around for quotes using an impartial service like the one on offer at Boilers Prices.